US20020189241A1 - Open-loop method and system for controlling the storage and release cycles of an emission control device - Google Patents
Open-loop method and system for controlling the storage and release cycles of an emission control device Download PDFInfo
- Publication number
- US20020189241A1 US20020189241A1 US09/884,331 US88433101A US2002189241A1 US 20020189241 A1 US20020189241 A1 US 20020189241A1 US 88433101 A US88433101 A US 88433101A US 2002189241 A1 US2002189241 A1 US 2002189241A1
- Authority
- US
- United States
- Prior art keywords
- value
- engine operating
- controller
- engine
- instantaneous
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
- F01N3/0828—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents characterised by the absorbed or adsorbed substances
- F01N3/0842—Nitrogen oxides
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
- F01N13/0093—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series the purifying devices are of the same type
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/021—Introducing corrections for particular conditions exterior to the engine
- F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
- F02D41/027—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus
- F02D41/0275—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus the exhaust gas treating apparatus being a NOx trap or adsorbent
- F02D41/028—Desulfurisation of NOx traps or adsorbent
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1439—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the position of the sensor
- F02D41/1441—Plural sensors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/146—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration
- F02D41/1461—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration of the exhaust gases emitted by the engine
- F02D41/1462—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration of the exhaust gases emitted by the engine with determination means using an estimation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
- F01N2570/04—Sulfur or sulfur oxides
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
- F01N2570/14—Nitrogen oxides
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/30—Controlling fuel injection
- F02D41/38—Controlling fuel injection of the high pressure type
- F02D2041/389—Controlling fuel injection of the high pressure type for injecting directly into the cylinder
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D2200/00—Input parameters for engine control
- F02D2200/02—Input parameters for engine control the parameters being related to the engine
- F02D2200/08—Exhaust gas treatment apparatus parameters
- F02D2200/0808—NOx storage capacity, i.e. maximum amount of NOx that can be stored on NOx trap
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D2200/00—Input parameters for engine control
- F02D2200/02—Input parameters for engine control the parameters being related to the engine
- F02D2200/08—Exhaust gas treatment apparatus parameters
- F02D2200/0818—SOx storage amount, e.g. for SOx trap or NOx trap
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/1446—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being exhaust temperatures
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
Definitions
- the invention relates to methods and systems for controlling the nominal storage and release times used in connection with an emission control device to facilitate “lean-burn” operation of an internal combustion engine.
- engine exhaust gas that includes a variety of constituents, including carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NO x ).
- CO carbon monoxide
- HC hydrocarbons
- NO x nitrogen oxides
- the rates at which the engine generates these constituents are dependent upon a variety of factors, such as engine operating speed and load, engine temperature, spark timing, and EGR.
- such engines often generate increased levels of one or more exhaust gas constituents, such as NO x , when the engine is operated in a lean-burn cycle, i.e., when engine operation includes engine operating conditions characterized by a ratio of intake air to injected fuel that is greater than the stoichiometric air-fuel ratio (a “lean” engine operating condition), for example, to achieve greater vehicle fuel economy.
- a lean-burn cycle i.e., when engine operation includes engine operating conditions characterized by a ratio of intake air to injected fuel that is greater than the stoichiometric air-fuel ratio (a “lean” engine operating condition), for example, to achieve greater vehicle fuel economy.
- Such systems often employ open-loop control of device storage and release times (also respectively known as device “fill” and “purge” times) so as to maximize the benefits of increased fuel efficiency obtained through lean engine operation without concomitantly increasing tailpipe emissions as the device becomes “filled.”
- the timing of each purge event must be controlled so that the device does not otherwise exceed its NO x storage capacity, because NO x would then pass through the device and effect an increase in tailpipe NO x emissions.
- the frequency of the purge is preferably controlled to avoid the purging of only partially filled devices, due to the fuel penalty associated with the purge event's enriched air-fuel mixture.
- 5,437,153 teaches use of a nominal NO x -storage capacity for its disclosed device which is significantly less than the actual NO x -storage capacity of the device, to thereby provide the device with a perfect instantaneous NO x -retaining efficiency, that is, so that the device is able to store all engine-generated NO x as long as the cumulative stored NO x remains below this nominal capacity.
- a purge event is scheduled to rejuvenate the device whenever accumulated estimates of engine-generated NO x reach the device's nominal capacity.
- the amount of the selected constituent gas that is actually stored in a given emission control device during vehicle operation depends on the concentration of the selected constituent gas in the engine feedgas, the exhaust flow rate, the ambient humidity, the device temperature, and other variables including the “poisoning” of the device with certain other constituents of the exhaust gas.
- concentration of the selected constituent gas in the engine feedgas the concentration of the selected constituent gas in the engine feedgas
- the exhaust flow rate the ambient humidity
- the device temperature and other variables including the “poisoning” of the device with certain other constituents of the exhaust gas.
- sulfur may be stored in the device and may correlatively cause a decrease in both the device's absolute capacity to store the selected exhaust gas constituent, and the device's instantaneous constituent-storing efficiency.
- U.S. Pat. No. 5,746,049 teaches a device desulfation method which includes raising the device temperature to at least 650° C. by introducing a source of secondary air into the exhaust upstream of the device when operating the engine with an enriched air-fuel mixture and relying on the resulting exothermic reaction to raise the device temperature to the desired level to purge the device of SO x .
- a method for controlling the fill and purge cycle of an emission control device disposed in an exhaust treatment system for an internal combustion engine.
- values representing an instantaneous rate at which a selected constituent of the engine-generated exhaust gas, such as NO x , is stored in the device, and the instantaneous capacity of the device to store the selected constituent are determined as a function of a calculated value representing an amount of SO x which has been accumulated in the device since an immediately prior desulfation event.
- the calculated value representing the amount of accumulated SO x is determined as a function of the instantaneous fuel flow rate during lean and stoichiometric engine operating conditions, preferably further adjusted to reflect the effects of instantaneous air-fuel ratio and instantaneous device temperature on the accumulation of SO x in the device.
- the calculated value representing the amount of accumulated SO x is used to schedule a device-regeneration or “desulfation” event.
- the value is preferably compared with a predetermined threshold value, with a desulfating engine operating condition being selected when the calculated accumulated SO x value exceeds the predetermined threshold value.
- the values representing the instantaneous storage rate for the selected constituent in the device, and the instantaneous storage capacity are further determined as a function of a determined value representing a permanent reduction in the constituent storage capacity of the device due to thermal effects and “penetrated” or diffused sulfur which cannot otherwise be purged during a nominal device-desulfation event.
- the Drawing is a schematic of an exemplary system for practicing the invention.
- an exemplary control system 10 for a four-cylinder gasoline-powered engine 12 for a motor vehicle includes an electronic engine controller 14 having ROM, RAM and a processor (“CPU”) as indicated, as well as an engine-off timer that provides a value for the elapsed time since the engine 12 was last turned off as a variable, “soak time.”
- the controller 14 controls the operation of each of a set of fuel injectors 16 .
- the fuel injectors 16 which are of conventional design, are each positioned to inject fuel into a respective cylinder 18 of the engine 12 in precise quantities as determined by the controller 14 .
- the controller 14 similarly controls the individual operation, i.e., timing, of the current directed through each of a set of spark plugs 20 in a known manner.
- the controller 14 also controls an electronic throttle 22 that regulates the mass flow of air into the engine 12 .
- An air mass flow sensor 24 positioned at the air intake of engine's intake manifold 26 , provides a signal regarding the air mass flow resulting from positioning of the engine's throttle 22 .
- the air flow signal from the air mass flow sensor 24 is utilized by the controller 14 to calculate an air mass value AM which is indicative of a mass of air flowing per unit time into the engine's induction system.
- a first oxygen sensor 28 coupled to the engine's exhaust manifold detects the oxygen content of the exhaust gas generated by the engine 12 and transmits a representative output signal to the controller 14 .
- a plurality of other sensors, including an engine speed sensor and an engine load sensor, indicated generally at 30 also generate additional signals in a known manner for use by the controller 14 .
- An exhaust system 32 transports exhaust gas produced from combustion of an air-fuel mixture in each cylinder 18 through a pair of emission control devices 34 , 36 .
- a second oxygen sensor 40 which may also be a switching-type HEGO sensor, is positioned in the exhaust system 32 between the first and second devices 34 , 36 .
- a third oxygen sensor 42 which likewise is a switching-type HEGO sensor, is positioned downstream of the second device 36 .
- a temperature sensor generates a signal representing the instantaneous temperature T of the second device 36 , also useful in optimizing device performance as described more fully below.
- the controller 14 Upon commencing lean engine operation, the controller 14 adjusts the output of the fuel injectors 16 to thereby achieve a lean air-fuel mixture for combustion within each cylinder 18 having an air-fuel ratio greater than about 1.3 times the stoichiometric air-fuel ratio.
- the controller 14 determines a value representing the instantaneous rate FG_NOX_RATE at which NO x is being generated by the engine 12 as a function of instantaneous engine operating conditions, which may include, without limitation, engine speed, engine load, air-fuel ratio, EGR, and spark.
- the controller 14 retrieves a stored estimate FG_NOX_RATE for the instantaneous NO x -generation rate from a lookup table stored in ROM based upon sensed values for engine speed N and engine load LOAD, wherein the stored estimates FG_NOX_RATE are originally obtained from engine mapping data.
- the controller 14 determines a value FG_NOX_RATE representing the instantaneous rate, in grams-per-hour, at which NO x is being generated by the engine 12 , preferably expressed by the following relationship:
- FNXXX1(N,LOAD) is a lookup table containing NO x emission rate values, in grams-per-hour, for current engine speed N and engine load LOAD;
- FNXXA( ⁇ ) is a lookup table for adjusting the FG_NOX_RATE value for air-fuel ratio which inherently adjusts the FG_NOX_RATE value for barometric pressure;
- FNXXB(EGRACT) is a lookup table for adjusting the FG_NOX_RATE value for actual exhaust gas recirculation percentage
- FNXXC(SPK_DELTA) is a lookup table for adjusting the FG_NOX_RATE value for the effect of knock sensor or hot open-loop induced spark retard, with NO x production being reduced with greater spark retard;
- FMXXD(ECT ⁇ 200) is a lookup table for adjusting the FG_NOX_RATE value for the effect of engine coolant temperature above 200° F.
- the determined feedgas NO x rate FG_NOX_RATE is further modified to reflect any reduction in feedgas NO x concentration upon passage of the exhaust gas through the first device 34 , as through use of a ROM-based lookup table of three-way catalyst efficiency in reducing NO x as a function of the current air-fuel ratio ⁇ , to obtain an adjusted instantaneous feedgas NO x rate ADJ_FG_NOX_RATE.
- the controller 14 also calculates an instantaneous value INCREMENTAL_NOX_RATE representing the incremental rate at which NO x is stored in the second device 36 during each background loop (e.g., t i,j ) executed by the controller 14 during a given lean operating condition, in accordance with the following formula:
- FNNXRT EFF(T,TOTAL_NOX) represents a lookup table for instantaneous device efficiency based on instantaneous device temperature T and a current value representing a cumulative amount TOTAL_NOX of NO x which has previously been stored in the second device 36 during a given lean engine operating condition, as described more fully below;
- FNSX_EFF(SOX_GRAMS) represents an empirically established capacity modifier which varies as a function of a current value SOX_GRAMS representing an amount of SO x which has accumulated within the second device 36 since a prior desulfating event, the value SOX_GRAMS being itself determined based on fuel flow, as described more fully below.
- the controller 14 thereafter updates a stored value TOTAL_NOX representing the cumulative amount of NO x which has been stored in the second device 36 during the given lean operating condition, in accordance with the following formula:
- the controller 14 determines a suitable value NOX_CAP representing the instantaneous NO x -storage capacity of the second device 36 .
- the value NOX_CAP varies as a function of second device temperature T, a determined value FNSX_CAP representing the amount of accumulated SO x , and a determined value PERMANENT_AGING representing an adjustment of NO x -storing capacity due to thermal aging and penetrated sulfur (which cannot otherwise be purged from the second device 36 during a desulfation event). More specifically, in a preferred embodiment, the instantaneous NO x -storage capacity value NOX_CAP is calculated in accordance with the following formula:
- ti NOX — CAP NOX — PURGE*FNNX — CAP ( T )* FNSX — CAP ( SOX — GRAMS )* PERMANENT — AGING
- NOX_PURGE is a predetermined threshold value for second device NO x -storage capacity
- FNNX_CAP(T) represents an empirically established capacity modifier which varies as a function of second device temperature T;
- FNSX_EFF(SOX_GRAMS) represents an empirically established capacity modifier which varies as a function of the current value SOX_GRAMS representing an amount of SO x which has accumulated within the second device 36 since a prior desulfating event;
- PERMANENT_AGING represents an empirically established capacity modifier which varies as a function of thermal aging and permanent sulfation of the second device 36 .
- the controller 14 compares the updated value TOTAL_NOX representing the cumulative amount of NO x stored in the second device 36 with the determined value NOX_CAP representing the second device's instantaneous NO x -storage capacity.
- the controller 14 discontinues the given lean operating condition and schedules a purge event when the updated value TOTAL_NOX exceeds the determined value NOX_CAP.
- the controller 14 determines values for FNSX_EFF and FNSX_CAP based upon the current value SOX_GRAMS representing the amount of SO x which has accumulated in the second device 36 since the last desulfation event, during both lean and stoichiometric engine operating conditions.
- the controller 14 determines the current value SOX_GRAMS by determining a value DELTA_SOX representing an instantaneous amount of SO x which is being added to the second device 36 during a given background loop time t i,j , using the following formula:
- DELTA — SOX FNSOXFUEL ( FUELFLOW — MFA AM, ⁇ ,t i,j )* FNSOXADJ ( ⁇ , T )* t i,j ,
- FUELFLOW_MFA represents a calculated value for current fuel flow rate based on current air mass flow AM, the current air-fuel ratio ⁇ , and the background loop time t i,j ;
- FNSOXFUEL (FUELFLOW_MFA) represents an empirically established generated-SO x modifier which varies as a function of the current fuel flow rate FUELFLOW_MFA;
- FNSOXADJ( ⁇ ,T) represents an empirically established generated-SO x modifier which varies as a function of both the current air-fuel ratio ⁇ and the instantaneous second device temperature T.
- the controller 14 thereafter updates a stored value SOX_GRAMS representing the cumulative amount of SO x which has accumulated in the second device 36 since the last desulfation event, in accordance with the following formula:
- the current value SOX_GRAMS is also used to schedule a desulfation event. Specifically, the controller 14 compares the current value SOX_GRAMS to a predetermined threshold value SOX_MAX_GRAMS. The controller 14 schedules a desulfation event when the current value SOX_GRAMS exceeds the predetermined threshold value SOX_MAX_GRAMS.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Exhaust Gas After Treatment (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
- 1. Technical Field
- The invention relates to methods and systems for controlling the nominal storage and release times used in connection with an emission control device to facilitate “lean-burn” operation of an internal combustion engine.
- 2. Background Art
- Generally, the operation of a vehicle's internal combustion engine produces engine exhaust gas that includes a variety of constituents, including carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). The rates at which the engine generates these constituents are dependent upon a variety of factors, such as engine operating speed and load, engine temperature, spark timing, and EGR. Moreover, such engines often generate increased levels of one or more exhaust gas constituents, such as NOx, when the engine is operated in a lean-burn cycle, i.e., when engine operation includes engine operating conditions characterized by a ratio of intake air to injected fuel that is greater than the stoichiometric air-fuel ratio (a “lean” engine operating condition), for example, to achieve greater vehicle fuel economy.
- In order to control these vehicle tailpipe emissions, the prior art teaches vehicle exhaust treatment systems that employ one or more three-way catalysts, also referred to as emission control devices, in an exhaust passage to store and release select exhaust gas constituents, such as NOx, depending upon engine operating conditions. For example, U.S. Pat. No. 5,437,153 teaches an emission control device which stores exhaust gas NOx when the exhaust gas is lean, and releases previously-stored NOx when the exhaust gas is either stoichiometric or “rich” of stoichiometric, i.e., when the ratio of intake air to injected fuel is at or below the stoichiometric air-fuel ratio. Such systems often employ open-loop control of device storage and release times (also respectively known as device “fill” and “purge” times) so as to maximize the benefits of increased fuel efficiency obtained through lean engine operation without concomitantly increasing tailpipe emissions as the device becomes “filled.” The timing of each purge event must be controlled so that the device does not otherwise exceed its NOx storage capacity, because NOx would then pass through the device and effect an increase in tailpipe NOx emissions. The frequency of the purge is preferably controlled to avoid the purging of only partially filled devices, due to the fuel penalty associated with the purge event's enriched air-fuel mixture.
- The prior art has recognized that the storage capacity of a given emission control device for a selected exhaust gas constituent is itself a function of many variables, including device temperature, device history, sulfation level, and the presence of any thermal damage to the device. Moreover, as the device approaches its maximum capacity, the prior art teaches that the incremental rate at which the device continues to store the selected exhaust gas constituent may begin to fall. Accordingly, U.S. Pat. No. 5,437,153 teaches use of a nominal NOx-storage capacity for its disclosed device which is significantly less than the actual NOx-storage capacity of the device, to thereby provide the device with a perfect instantaneous NOx-retaining efficiency, that is, so that the device is able to store all engine-generated NOx as long as the cumulative stored NOx remains below this nominal capacity. A purge event is scheduled to rejuvenate the device whenever accumulated estimates of engine-generated NOx reach the device's nominal capacity.
- The amount of the selected constituent gas that is actually stored in a given emission control device during vehicle operation depends on the concentration of the selected constituent gas in the engine feedgas, the exhaust flow rate, the ambient humidity, the device temperature, and other variables including the “poisoning” of the device with certain other constituents of the exhaust gas. For example, when an internal combustion engine is operated using a fuel containing sulfur, the prior art teaches that sulfur may be stored in the device and may correlatively cause a decrease in both the device's absolute capacity to store the selected exhaust gas constituent, and the device's instantaneous constituent-storing efficiency. When such device sulfation exceeds a critical level, the stored SOx must be “burned off” or released during a desulfation event, during which device temperatures are raised above perhaps about 650° C. in the presence of excess HC and CO. By way of example only, U.S. Pat. No. 5,746,049 teaches a device desulfation method which includes raising the device temperature to at least 650° C. by introducing a source of secondary air into the exhaust upstream of the device when operating the engine with an enriched air-fuel mixture and relying on the resulting exothermic reaction to raise the device temperature to the desired level to purge the device of SOx.
- Thus, it will be appreciated that both the device capacity to store the selected exhaust gas constituent, and the actual quantity of the selected constituent stored in the device, are complex functions of many variables that prior art accumulation-model-based systems do not take into account. The inventors herein have recognized a need for a method and system for controlling an internal combustion engine whose exhaust gas is received by an emission control device which can more accurately determine the amount of the selected exhaust gas constituent, such as NOx, stored in an emission control device during lean engine operation and which, in response, can more closely regulate device fill and purge times to optimize tailpipe emissions.
- Under the invention, a method is provided for controlling the fill and purge cycle of an emission control device disposed in an exhaust treatment system for an internal combustion engine. Under the invention, values representing an instantaneous rate at which a selected constituent of the engine-generated exhaust gas, such as NOx, is stored in the device, and the instantaneous capacity of the device to store the selected constituent, are determined as a function of a calculated value representing an amount of SOx which has been accumulated in the device since an immediately prior desulfation event. More specifically, in a preferred embodiment, the calculated value representing the amount of accumulated SOx is determined as a function of the instantaneous fuel flow rate during lean and stoichiometric engine operating conditions, preferably further adjusted to reflect the effects of instantaneous air-fuel ratio and instantaneous device temperature on the accumulation of SOx in the device.
- In accordance with another feature of the invention, in a preferred embodiment, the calculated value representing the amount of accumulated SOx is used to schedule a device-regeneration or “desulfation” event. Specifically, the value is preferably compared with a predetermined threshold value, with a desulfating engine operating condition being selected when the calculated accumulated SOx value exceeds the predetermined threshold value.
- In accordance with another feature of the invention, the values representing the instantaneous storage rate for the selected constituent in the device, and the instantaneous storage capacity, are further determined as a function of a determined value representing a permanent reduction in the constituent storage capacity of the device due to thermal effects and “penetrated” or diffused sulfur which cannot otherwise be purged during a nominal device-desulfation event.
- The above object and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.
- The Drawing is a schematic of an exemplary system for practicing the invention.
- Referring to the Drawing, an
exemplary control system 10 for a four-cylinder gasoline-poweredengine 12 for a motor vehicle includes anelectronic engine controller 14 having ROM, RAM and a processor (“CPU”) as indicated, as well as an engine-off timer that provides a value for the elapsed time since theengine 12 was last turned off as a variable, “soak time.” Thecontroller 14 controls the operation of each of a set offuel injectors 16. Thefuel injectors 16, which are of conventional design, are each positioned to inject fuel into arespective cylinder 18 of theengine 12 in precise quantities as determined by thecontroller 14. Thecontroller 14 similarly controls the individual operation, i.e., timing, of the current directed through each of a set ofspark plugs 20 in a known manner. - The
controller 14 also controls anelectronic throttle 22 that regulates the mass flow of air into theengine 12. An airmass flow sensor 24, positioned at the air intake of engine'sintake manifold 26, provides a signal regarding the air mass flow resulting from positioning of the engine'sthrottle 22. The air flow signal from the airmass flow sensor 24 is utilized by thecontroller 14 to calculate an air mass value AM which is indicative of a mass of air flowing per unit time into the engine's induction system. - A
first oxygen sensor 28 coupled to the engine's exhaust manifold detects the oxygen content of the exhaust gas generated by theengine 12 and transmits a representative output signal to thecontroller 14. Thefirst oxygen sensor 28 provides feedback to thecontroller 14 for improved control of the air-fuel ratio of the air-fuel mixture supplied to theengine 12, particularly during operation of theengine 12 at or about the stoichiometric air-fuel ratio (λ=1.00). A plurality of other sensors, including an engine speed sensor and an engine load sensor, indicated generally at 30, also generate additional signals in a known manner for use by thecontroller 14. - An
exhaust system 32 transports exhaust gas produced from combustion of an air-fuel mixture in eachcylinder 18 through a pair ofemission control devices second oxygen sensor 40, which may also be a switching-type HEGO sensor, is positioned in theexhaust system 32 between the first andsecond devices third oxygen sensor 42, which likewise is a switching-type HEGO sensor, is positioned downstream of thesecond device 36. In accordance with another feature of the invention, a temperature sensor generates a signal representing the instantaneous temperature T of thesecond device 36, also useful in optimizing device performance as described more fully below. - Upon commencing lean engine operation, the
controller 14 adjusts the output of thefuel injectors 16 to thereby achieve a lean air-fuel mixture for combustion within eachcylinder 18 having an air-fuel ratio greater than about 1.3 times the stoichiometric air-fuel ratio. In accordance with the invention, for each subsequent background loop of thecontroller 14 during lean engine operation, thecontroller 14 determines a value representing the instantaneous rate FG_NOX_RATE at which NOx is being generated by theengine 12 as a function of instantaneous engine operating conditions, which may include, without limitation, engine speed, engine load, air-fuel ratio, EGR, and spark. - By way of example only, in a preferred embodiment, the
controller 14 retrieves a stored estimate FG_NOX_RATE for the instantaneous NOx-generation rate from a lookup table stored in ROM based upon sensed values for engine speed N and engine load LOAD, wherein the stored estimates FG_NOX_RATE are originally obtained from engine mapping data. - During a first engine operating condition, characterized by combustion in the
engine 12 of a lean air-fuel mixture, thecontroller 14 determines a value FG_NOX_RATE representing the instantaneous rate, in grams-per-hour, at which NOx is being generated by theengine 12, preferably expressed by the following relationship: - FG — NOX — RATE=FNXXX1(N,LOAD)*FNXXA(λ)*FNXXB(EGRACT)*FNXXC(SPK — DELTA)*FMXXD(ECT−200)
- where:
- FNXXX1(N,LOAD) is a lookup table containing NOx emission rate values, in grams-per-hour, for current engine speed N and engine load LOAD;
- FNXXA(λ) is a lookup table for adjusting the FG_NOX_RATE value for air-fuel ratio which inherently adjusts the FG_NOX_RATE value for barometric pressure;
- FNXXB(EGRACT) is a lookup table for adjusting the FG_NOX_RATE value for actual exhaust gas recirculation percentage;
- FNXXC(SPK_DELTA) is a lookup table for adjusting the FG_NOX_RATE value for the effect of knock sensor or hot open-loop induced spark retard, with NOx production being reduced with greater spark retard; and
- FMXXD(ECT−200) is a lookup table for adjusting the FG_NOX_RATE value for the effect of engine coolant temperature above 200° F.
- Preferably, the determined feedgas NOx rate FG_NOX_RATE is further modified to reflect any reduction in feedgas NOx concentration upon passage of the exhaust gas through the
first device 34, as through use of a ROM-based lookup table of three-way catalyst efficiency in reducing NOx as a function of the current air-fuel ratio λ, to obtain an adjusted instantaneous feedgas NOx rate ADJ_FG_NOX_RATE. - The
controller 14 also calculates an instantaneous value INCREMENTAL_NOX_RATE representing the incremental rate at which NOx is stored in thesecond device 36 during each background loop (e.g., ti,j) executed by thecontroller 14 during a given lean operating condition, in accordance with the following formula: - INCREMENTAL — NOX — RATE=ADJ — FG — NOX — RATE*FNNXRT — EFF(T,TOTAL — NOX)*FNSX — EFF(SOX — GRAMS),
- where:
- FNNXRT EFF(T,TOTAL_NOX) represents a lookup table for instantaneous device efficiency based on instantaneous device temperature T and a current value representing a cumulative amount TOTAL_NOX of NOx which has previously been stored in the
second device 36 during a given lean engine operating condition, as described more fully below; and - FNSX_EFF(SOX_GRAMS) represents an empirically established capacity modifier which varies as a function of a current value SOX_GRAMS representing an amount of SOx which has accumulated within the
second device 36 since a prior desulfating event, the value SOX_GRAMS being itself determined based on fuel flow, as described more fully below. - The
controller 14 thereafter updates a stored value TOTAL_NOX representing the cumulative amount of NOx which has been stored in thesecond device 36 during the given lean operating condition, in accordance with the following formula: - TOTAL — NOX←TOTAL — NOX+INCREMENTAL — NOX — RATE*t i,j.
- The
controller 14 then determines a suitable value NOX_CAP representing the instantaneous NOx-storage capacity of thesecond device 36. By way of example only, in a preferred embodiment, the value NOX_CAP varies as a function of second device temperature T, a determined value FNSX_CAP representing the amount of accumulated SOx, and a determined value PERMANENT_AGING representing an adjustment of NOx-storing capacity due to thermal aging and penetrated sulfur (which cannot otherwise be purged from thesecond device 36 during a desulfation event). More specifically, in a preferred embodiment, the instantaneous NOx-storage capacity value NOX_CAP is calculated in accordance with the following formula: - tiNOX — CAP=NOX — PURGE*FNNX — CAP(T)*FNSX — CAP(SOX — GRAMS)*PERMANENT — AGING
- where:
- NOX_PURGE is a predetermined threshold value for second device NOx-storage capacity;
- FNNX_CAP(T) represents an empirically established capacity modifier which varies as a function of second device temperature T;
- FNSX_EFF(SOX_GRAMS) represents an empirically established capacity modifier which varies as a function of the current value SOX_GRAMS representing an amount of SOx which has accumulated within the
second device 36 since a prior desulfating event; and - PERMANENT_AGING represents an empirically established capacity modifier which varies as a function of thermal aging and permanent sulfation of the
second device 36. - The
controller 14 then compares the updated value TOTAL_NOX representing the cumulative amount of NOx stored in thesecond device 36 with the determined value NOX_CAP representing the second device's instantaneous NOx-storage capacity. Thecontroller 14 discontinues the given lean operating condition and schedules a purge event when the updated value TOTAL_NOX exceeds the determined value NOX_CAP. - As noted above, the
controller 14 determines values for FNSX_EFF and FNSX_CAP based upon the current value SOX_GRAMS representing the amount of SOx which has accumulated in thesecond device 36 since the last desulfation event, during both lean and stoichiometric engine operating conditions. In accordance with another feature of the invention, thecontroller 14 determines the current value SOX_GRAMS by determining a value DELTA_SOX representing an instantaneous amount of SOx which is being added to thesecond device 36 during a given background loop time ti,j, using the following formula: - DELTA — SOX=FNSOXFUEL(FUELFLOW — MFA AM,λ,t i,j)*FNSOXADJ(λ,T)*t i,j,
- where:
- FUELFLOW_MFA represents a calculated value for current fuel flow rate based on current air mass flow AM, the current air-fuel ratio λ, and the background loop time ti,j;
- FNSOXFUEL(FUELFLOW_MFA) represents an empirically established generated-SOx modifier which varies as a function of the current fuel flow rate FUELFLOW_MFA; and
- FNSOXADJ(λ,T) represents an empirically established generated-SOx modifier which varies as a function of both the current air-fuel ratio λ and the instantaneous second device temperature T.
- The
controller 14 thereafter updates a stored value SOX_GRAMS representing the cumulative amount of SOx which has accumulated in thesecond device 36 since the last desulfation event, in accordance with the following formula: - SOX — GRAMS←SOX — GRAMS+DELTA — SOX.
- In accordance with a further benefit of the invention, the current value SOX_GRAMS is also used to schedule a desulfation event. Specifically, the
controller 14 compares the current value SOX_GRAMS to a predetermined threshold value SOX_MAX_GRAMS. Thecontroller 14 schedules a desulfation event when the current value SOX_GRAMS exceeds the predetermined threshold value SOX_MAX_GRAMS. - While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
Claims (16)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/884,331 US6490860B1 (en) | 2001-06-19 | 2001-06-19 | Open-loop method and system for controlling the storage and release cycles of an emission control device |
DE10223984A DE10223984A1 (en) | 2001-06-19 | 2002-05-29 | Method and system for open control of the storage and release cycles of an exhaust gas control device |
GB0213308A GB2380432B (en) | 2001-06-19 | 2002-06-11 | A method and system for controlling an emission control device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/884,331 US6490860B1 (en) | 2001-06-19 | 2001-06-19 | Open-loop method and system for controlling the storage and release cycles of an emission control device |
Publications (2)
Publication Number | Publication Date |
---|---|
US6490860B1 US6490860B1 (en) | 2002-12-10 |
US20020189241A1 true US20020189241A1 (en) | 2002-12-19 |
Family
ID=25384399
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/884,331 Expired - Fee Related US6490860B1 (en) | 2001-06-19 | 2001-06-19 | Open-loop method and system for controlling the storage and release cycles of an emission control device |
Country Status (3)
Country | Link |
---|---|
US (1) | US6490860B1 (en) |
DE (1) | DE10223984A1 (en) |
GB (1) | GB2380432B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110185708A1 (en) * | 2010-01-29 | 2011-08-04 | Eaton Corporation | Adaptive Desulfation Control Algorithm |
WO2014007749A1 (en) * | 2012-07-06 | 2014-01-09 | Scania Cv Ab | Method for estimating quantity of sulphur accumulated in exhaust after treatment system |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4415648B2 (en) * | 2003-11-05 | 2010-02-17 | いすゞ自動車株式会社 | Sulfur purge control method and exhaust gas purification system |
WO2005124113A2 (en) * | 2004-06-08 | 2005-12-29 | Cummins, Inc. | Method for modifying trigger level for adsorber regeneration |
US7594392B2 (en) | 2006-11-07 | 2009-09-29 | Cummins, Inc. | System for controlling adsorber regeneration |
US7654076B2 (en) | 2006-11-07 | 2010-02-02 | Cummins, Inc. | System for controlling absorber regeneration |
US7533523B2 (en) | 2006-11-07 | 2009-05-19 | Cummins, Inc. | Optimized desulfation trigger control for an adsorber |
US7654079B2 (en) | 2006-11-07 | 2010-02-02 | Cummins, Inc. | Diesel oxidation catalyst filter heating system |
US7707826B2 (en) | 2006-11-07 | 2010-05-04 | Cummins, Inc. | System for controlling triggering of adsorber regeneration |
EP3346105B1 (en) * | 2011-04-05 | 2020-06-10 | Cummins Emission Solutions, Inc. | System, method, and apparatus for aftertreatment system monitoring |
DE102014210841A1 (en) * | 2014-06-06 | 2015-12-17 | Robert Bosch Gmbh | Method for determining a nitrogen oxide emission during operation of an internal combustion engine |
Family Cites Families (154)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3696618A (en) | 1971-04-19 | 1972-10-10 | Universal Oil Prod Co | Control system for an engine system |
US4036014A (en) | 1973-05-30 | 1977-07-19 | Nissan Motor Co., Ltd. | Method of reducing emission of pollutants from multi-cylinder engine |
GB1490746A (en) | 1973-11-08 | 1977-11-02 | Nissan Motor | Method of and a system for reducing the quantities of noxious gases emitted into the atmosphere from an internal combustion engine |
DE2444334A1 (en) | 1974-09-17 | 1976-03-25 | Bosch Gmbh Robert | METHOD AND EQUIPMENT FOR MONITORING THE ACTIVITY OF CATALYTIC REACTORS |
DE2702863C2 (en) | 1977-01-25 | 1986-06-05 | Robert Bosch Gmbh, 7000 Stuttgart | Method and device for regulating the mixture ratio components of the operating mixture fed to an internal combustion engine |
US4167924A (en) | 1977-10-03 | 1979-09-18 | General Motors Corporation | Closed loop fuel control system having variable control authority |
US4186296A (en) | 1977-12-19 | 1980-01-29 | Crump John M Jr | Vehicle energy conservation indicating device and process for use |
JPS5537562A (en) | 1978-09-08 | 1980-03-15 | Nippon Denso Co Ltd | Air-fuel ratio control system |
DE3104196C2 (en) | 1981-02-06 | 1988-07-28 | Bayerische Motoren Werke AG, 8000 München | Display device for automobiles |
CH668620A5 (en) | 1984-04-12 | 1989-01-13 | Daimler Benz Ag | METHOD FOR CHECKING AND ADJUSTING CATALYTIC EXHAUST GAS PURIFICATION PLANTS OF COMBUSTION ENGINES. |
JPH0697002B2 (en) | 1984-11-30 | 1994-11-30 | 日本電装株式会社 | Air-fuel ratio sensor pass / fail judgment device |
JPS62162746A (en) | 1986-01-10 | 1987-07-18 | Nissan Motor Co Ltd | Air-fuel ratio control device |
JPS6383415U (en) | 1986-11-20 | 1988-06-01 | ||
JP2638793B2 (en) | 1987-01-14 | 1997-08-06 | 日産自動車株式会社 | Air-fuel ratio control device |
CA1298957C (en) | 1987-01-27 | 1992-04-21 | Motonobu Kobayashi | Method for removal of nitrogen oxides from exhaust gas of diesel engine |
JP2526591B2 (en) | 1987-07-20 | 1996-08-21 | トヨタ自動車株式会社 | Air-fuel ratio control device for internal combustion engine |
GB8816667D0 (en) | 1988-07-13 | 1988-08-17 | Johnson Matthey Plc | Improvements in pollution control |
US5088281A (en) | 1988-07-20 | 1992-02-18 | Toyota Jidosha Kabushiki Kaisha | Method and apparatus for determining deterioration of three-way catalysts in double air-fuel ratio sensor system |
CA2024154C (en) | 1989-08-31 | 1995-02-14 | Senshi Kasahara | Catalyst for reducing nitrogen oxides from exhaust gas |
US5010051A (en) | 1989-11-08 | 1991-04-23 | Engelhard Corporation | Staged three-way conversion catalyst and method of using the same |
JP2830464B2 (en) | 1989-12-06 | 1998-12-02 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
US5189876A (en) | 1990-02-09 | 1993-03-02 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification system for an internal combustion engine |
GB9003235D0 (en) | 1990-02-13 | 1990-04-11 | Lucas Ind Plc | Exhaust gas catalyst monitoring |
JP2745761B2 (en) | 1990-02-27 | 1998-04-28 | 株式会社デンソー | Catalyst deterioration determination device for internal combustion engine |
US5222471A (en) | 1992-09-18 | 1993-06-29 | Kohler Co. | Emission control system for an internal combustion engine |
US5357750A (en) | 1990-04-12 | 1994-10-25 | Ngk Spark Plug Co., Ltd. | Method for detecting deterioration of catalyst and measuring conversion efficiency thereof with an air/fuel ratio sensor |
JP2712758B2 (en) | 1990-05-28 | 1998-02-16 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JPH0726580B2 (en) | 1990-11-20 | 1995-03-29 | トヨタ自動車株式会社 | Device for determining catalyst deterioration of internal combustion engine |
DE4039762A1 (en) | 1990-12-13 | 1992-06-17 | Bosch Gmbh Robert | METHOD AND DEVICE FOR CHECKING THE AGING STATE OF A CATALYST |
US5174111A (en) | 1991-01-31 | 1992-12-29 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification system for an internal combustion engine |
US5201802A (en) | 1991-02-04 | 1993-04-13 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification system for an internal combustion engine |
US5643133A (en) | 1991-02-25 | 1997-07-01 | Hitachi, Ltd. | Change gear control device using acceleration and gear ratio as parameters for automatic transmission in a motor vehicle and the method therefor |
JP2887933B2 (en) | 1991-03-13 | 1999-05-10 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
US5147756A (en) | 1991-04-11 | 1992-09-15 | E. I. Du Pont De Nemours And Company | Stabilized, aqueous hydrazide solutions for photographic elements |
US5272871A (en) | 1991-05-24 | 1993-12-28 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Method and apparatus for reducing nitrogen oxides from internal combustion engine |
EP0683311A1 (en) | 1991-06-03 | 1995-11-22 | Isuzu Motors Limited | DEVICE FOR REDUCING NO x? |
DE4128823C2 (en) | 1991-08-30 | 2000-06-29 | Bosch Gmbh Robert | Method and device for determining the storage capacity of a catalytic converter |
JP3135147B2 (en) | 1991-09-17 | 2001-02-13 | 豊田工機株式会社 | Parent and child hand |
AU650794B2 (en) | 1991-10-03 | 1994-06-30 | Toyota Jidosha Kabushiki Kaisha | Device for purifying exhaust of internal combustion engine |
JPH05106430A (en) | 1991-10-16 | 1993-04-27 | Toyota Central Res & Dev Lab Inc | Nitrogen oxide reducing device for internal combustion engine |
US5325664A (en) | 1991-10-18 | 1994-07-05 | Honda Giken Kogyo Kabushiki Kaisha | System for determining deterioration of catalysts of internal combustion engines |
DE69218183T2 (en) | 1991-12-27 | 1997-07-31 | Toyoda Chuo Kenkyusho Kk | DEVICE FOR EMISSION CONTROL IN AN INTERNAL COMBUSTION ENGINE |
DE69326417T2 (en) | 1992-06-12 | 2000-04-13 | Toyota Motor Co Ltd | EXHAUST EMISSION CONTROL SYSTEM FOR COMBUSTION ENGINES |
DE69326217T3 (en) | 1992-06-12 | 2009-11-12 | Toyota Jidosha Kabushiki Kaisha, Toyota-shi | EXHAUST EMISSION CONTROL SYSTEM FOR INTERNAL COMBUSTION ENGINES |
US5622047A (en) | 1992-07-03 | 1997-04-22 | Nippondenso Co., Ltd. | Method and apparatus for detecting saturation gas amount absorbed by catalytic converter |
JP2605586B2 (en) | 1992-07-24 | 1997-04-30 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
US5433074A (en) | 1992-07-30 | 1995-07-18 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification device for an engine |
JP2605553B2 (en) | 1992-08-04 | 1997-04-30 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP2692530B2 (en) | 1992-09-02 | 1997-12-17 | トヨタ自動車株式会社 | Internal combustion engine |
JP3074975B2 (en) | 1992-11-04 | 2000-08-07 | スズキ株式会社 | Catalyst deterioration determination device for internal combustion engine |
US5473890A (en) | 1992-12-03 | 1995-12-12 | Toyota Jidosha Kabushiki Kaisha | Exhaust purification device of internal combustion engine |
JP2624107B2 (en) | 1992-12-09 | 1997-06-25 | トヨタ自動車株式会社 | Catalyst deterioration detection device |
US5483795A (en) | 1993-01-19 | 1996-01-16 | Toyota Jidosha Kabushiki Kaisha | Exhaust purification device of internal combustion engine |
US5426934A (en) | 1993-02-10 | 1995-06-27 | Hitachi America, Ltd. | Engine and emission monitoring and control system utilizing gas sensors |
JP2605579B2 (en) | 1993-05-31 | 1997-04-30 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP3266699B2 (en) | 1993-06-22 | 2002-03-18 | 株式会社日立製作所 | Catalyst evaluation method, catalyst efficiency control method, and NOx purification catalyst evaluation apparatus |
US5359852A (en) | 1993-09-07 | 1994-11-01 | Ford Motor Company | Air fuel ratio feedback control |
US5419122A (en) | 1993-10-04 | 1995-05-30 | Ford Motor Company | Detection of catalytic converter operability by light-off time determination |
JP3344040B2 (en) | 1993-11-25 | 2002-11-11 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP3244584B2 (en) | 1994-02-10 | 2002-01-07 | 株式会社日立製作所 | Diagnosis method and apparatus for engine exhaust gas purification device |
US5414994A (en) | 1994-02-15 | 1995-05-16 | Ford Motor Company | Method and apparatus to limit a midbed temperature of a catalytic converter |
JP3248806B2 (en) | 1994-03-18 | 2002-01-21 | 本田技研工業株式会社 | Exhaust gas purification device for internal combustion engine |
US5803048A (en) | 1994-04-08 | 1998-09-08 | Honda Giken Kogyo Kabushiki Kaisha | System and method for controlling air-fuel ratio in internal combustion engine |
KR0150432B1 (en) | 1994-05-10 | 1998-10-01 | 나까무라 유이찌 | Apparatus and method for injernal combustion engine |
EP0687809B1 (en) | 1994-06-17 | 2001-08-29 | Hitachi, Ltd. | An output torque control apparatus and method for an internal combustion engine |
US5657625A (en) | 1994-06-17 | 1997-08-19 | Mitsubishi Jidosha Kogyo Kabushiki Kaisha | Apparatus and method for internal combustion engine control |
JP3228006B2 (en) | 1994-06-30 | 2001-11-12 | トヨタ自動車株式会社 | Exhaust purification element deterioration detection device for internal combustion engine |
US5626117A (en) | 1994-07-08 | 1997-05-06 | Ford Motor Company | Electronic ignition system with modulated cylinder-to-cylinder timing |
US5452576A (en) | 1994-08-09 | 1995-09-26 | Ford Motor Company | Air/fuel control with on-board emission measurement |
JP3427581B2 (en) | 1994-09-13 | 2003-07-22 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JPH08144746A (en) | 1994-11-25 | 1996-06-04 | Honda Motor Co Ltd | Air-fuel ratio control device for internal combustion engine |
JP3440654B2 (en) | 1994-11-25 | 2003-08-25 | トヨタ自動車株式会社 | Exhaust gas purification device |
JP3467657B2 (en) | 1994-12-26 | 2003-11-17 | 株式会社日立製作所 | Exhaust control device for internal combustion engine |
US5569848A (en) | 1995-01-06 | 1996-10-29 | Sharp; Everett H. | System, method and apparatus for monitoring tire inflation pressure in a vehicle tire and wheel assembly |
JP3079933B2 (en) | 1995-02-14 | 2000-08-21 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
WO1996028646A1 (en) | 1995-03-16 | 1996-09-19 | Hyundai Motor Company | Apparatus and method for judging deterioration of catalysts device and oxygen content sensing device |
JP2836522B2 (en) | 1995-03-24 | 1998-12-14 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP2836523B2 (en) | 1995-03-24 | 1998-12-14 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP2827954B2 (en) | 1995-03-28 | 1998-11-25 | トヨタ自動車株式会社 | NOx absorbent deterioration detection device |
US5554269A (en) | 1995-04-11 | 1996-09-10 | Gas Research Institute | Nox sensor using electrochemical reactions and differential pulse voltammetry (DPV) |
JPH08338297A (en) | 1995-04-12 | 1996-12-24 | Toyota Motor Corp | Catalyst deterioration judging device |
JP3542404B2 (en) | 1995-04-26 | 2004-07-14 | 本田技研工業株式会社 | Air-fuel ratio control device for internal combustion engine |
JP3498817B2 (en) | 1995-06-14 | 2004-02-23 | 株式会社デンソー | Exhaust system failure diagnosis device for internal combustion engine |
US5626014A (en) | 1995-06-30 | 1997-05-06 | Ford Motor Company | Catalyst monitor based on a thermal power model |
GB2304602A (en) | 1995-08-26 | 1997-03-26 | Ford Motor Co | Engine with cylinder deactivation |
JP3603422B2 (en) | 1995-10-23 | 2004-12-22 | 日産自動車株式会社 | Engine catalyst temperature estimation device and catalyst diagnosis device |
JP3196606B2 (en) | 1995-10-26 | 2001-08-06 | トヨタ自動車株式会社 | Catalyst deterioration determination device for internal combustion engine |
JPH09126040A (en) | 1995-11-02 | 1997-05-13 | Hitachi Ltd | Control device for internal combustion engine |
US5598703A (en) | 1995-11-17 | 1997-02-04 | Ford Motor Company | Air/fuel control system for an internal combustion engine |
DE19543219C1 (en) | 1995-11-20 | 1996-12-05 | Daimler Benz Ag | Diesel engine operating method |
JPH09158713A (en) | 1995-12-07 | 1997-06-17 | Toyota Motor Corp | Catalyst deterioration judging device of internal combustion engine |
DE19607151C1 (en) | 1996-02-26 | 1997-07-10 | Siemens Ag | Regeneration of nitrogen oxide storage catalyst |
JP3674017B2 (en) | 1996-03-19 | 2005-07-20 | 株式会社デンソー | Catalyst degradation detection device for exhaust gas purification |
JP3713831B2 (en) | 1996-04-19 | 2005-11-09 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
GB2328626B (en) * | 1996-04-26 | 1999-08-11 | Komatsu Mfg Co Ltd | Apparatus and method for regenerating NOx catalyst for diesel engine |
US5704339A (en) | 1996-04-26 | 1998-01-06 | Ford Global Technologies, Inc. | method and apparatus for improving vehicle fuel economy |
US5792436A (en) | 1996-05-13 | 1998-08-11 | Engelhard Corporation | Method for using a regenerable catalyzed trap |
WO1997047864A1 (en) | 1996-06-10 | 1997-12-18 | Hitachi, Ltd. | Exhaust gas purification apparatus of internal combustion engine and catalyst for purifying exhaust gas of internal combustion engine |
JP3581762B2 (en) | 1996-06-20 | 2004-10-27 | トヨタ自動車株式会社 | Air-fuel ratio control device for internal combustion engine |
JPH1071325A (en) | 1996-06-21 | 1998-03-17 | Ngk Insulators Ltd | Method for controlling engine exhaust gas system and method for detecting deterioration in catalyst/ adsorption means |
JPH1068346A (en) | 1996-06-21 | 1998-03-10 | Ngk Insulators Ltd | Control method for engine exhaust gas system |
DE19630940C2 (en) | 1996-07-31 | 1999-03-04 | Siemens Ag | Procedure for checking the catalyst efficiency |
US5966930A (en) | 1996-08-22 | 1999-10-19 | Honda Giken Kogyo Kabushiki Kaisha | Catalyst deterioration-determining system for internal combustion engines |
DE19640161A1 (en) | 1996-09-28 | 1998-04-02 | Volkswagen Ag | NOx emission control process |
US5771685A (en) | 1996-10-16 | 1998-06-30 | Ford Global Technologies, Inc. | Method for monitoring the performance of a NOx trap |
US5743084A (en) | 1996-10-16 | 1998-04-28 | Ford Global Technologies, Inc. | Method for monitoring the performance of a nox trap |
US6003308A (en) | 1996-10-29 | 1999-12-21 | Honda Giken Kogyo Kabushiki Kaisha | Air-fuel ratio control system for internal combustion engines |
JP3557815B2 (en) | 1996-11-01 | 2004-08-25 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP3332761B2 (en) | 1996-11-08 | 2002-10-07 | 日本特殊陶業株式会社 | Oxygen concentration / nitrogen oxide concentration measurement method and device |
US5722236A (en) | 1996-12-13 | 1998-03-03 | Ford Global Technologies, Inc. | Adaptive exhaust temperature estimation and control |
US5746049A (en) | 1996-12-13 | 1998-05-05 | Ford Global Technologies, Inc. | Method and apparatus for estimating and controlling no x trap temperature |
US5831267A (en) | 1997-02-24 | 1998-11-03 | Envirotest Systems Corp. | Method and apparatus for remote measurement of exhaust gas |
JP3656354B2 (en) | 1997-02-26 | 2005-06-08 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
US5842340A (en) | 1997-02-26 | 1998-12-01 | Motorola Inc. | Method for controlling the level of oxygen stored by a catalyst within a catalytic converter |
US5842339A (en) | 1997-02-26 | 1998-12-01 | Motorola Inc. | Method for monitoring the performance of a catalytic converter |
JP3645704B2 (en) | 1997-03-04 | 2005-05-11 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP3067685B2 (en) * | 1997-03-31 | 2000-07-17 | 三菱自動車工業株式会社 | Exhaust purification system for spark ignition type direct injection type internal combustion engine |
US5832722A (en) | 1997-03-31 | 1998-11-10 | Ford Global Technologies, Inc. | Method and apparatus for maintaining catalyst efficiency of a NOx trap |
JP4034375B2 (en) | 1997-04-03 | 2008-01-16 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
DE19714293C1 (en) | 1997-04-07 | 1998-09-03 | Siemens Ag | Procedure for checking the convertibility of a catalytic converter |
US6105365A (en) | 1997-04-08 | 2000-08-22 | Engelhard Corporation | Apparatus, method, and system for concentrating adsorbable pollutants and abatement thereof |
JP3237607B2 (en) | 1997-05-26 | 2001-12-10 | トヨタ自動車株式会社 | Catalyst poisoning regeneration equipment for internal combustion engines |
EP0892158B1 (en) | 1997-07-19 | 2003-02-12 | Volkswagen Aktiengesellschaft | Method and device to monitor the desulphurization of NOx storage catalytic converters |
DE19736233C2 (en) | 1997-08-20 | 2001-03-29 | Siemens Ag | Procedure for checking a catalyst |
EP0898067B1 (en) | 1997-08-21 | 2004-03-17 | Nissan Motor Co., Ltd. | Exhaust gas purifying system of internal combustion engine |
JP3264226B2 (en) | 1997-08-25 | 2002-03-11 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
US5974788A (en) | 1997-08-29 | 1999-11-02 | Ford Global Technologies, Inc. | Method and apparatus for desulfating a nox trap |
US5983627A (en) | 1997-09-02 | 1999-11-16 | Ford Global Technologies, Inc. | Closed loop control for desulfating a NOx trap |
DE19739848A1 (en) | 1997-09-11 | 1999-03-18 | Bosch Gmbh Robert | Internal combustion engine, in particular for a motor vehicle |
US6138453A (en) | 1997-09-19 | 2000-10-31 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification device for an internal combustion engine |
JP3430879B2 (en) | 1997-09-19 | 2003-07-28 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
US6148612A (en) | 1997-10-13 | 2000-11-21 | Denso Corporation | Engine exhaust gas control system having NOx catalyst |
JP3549147B2 (en) | 1997-11-25 | 2004-08-04 | 本田技研工業株式会社 | Device for detecting catalyst deterioration of internal combustion engine for natural gas |
US6092021A (en) | 1997-12-01 | 2000-07-18 | Freightliner Corporation | Fuel use efficiency system for a vehicle for assisting the driver to improve fuel economy |
US5910096A (en) | 1997-12-22 | 1999-06-08 | Ford Global Technologies, Inc. | Temperature control system for emission device coupled to direct injection engines |
DE19801626B4 (en) | 1998-01-17 | 2010-08-12 | Robert Bosch Gmbh | Diagnosis of a NOx storage catalytic converter in the operation of internal combustion engines |
DE19801625A1 (en) | 1998-01-17 | 1999-07-22 | Bosch Gmbh Robert | Monitoring method for NOx storage catalytic convertors |
JP3591283B2 (en) | 1998-01-29 | 2004-11-17 | 日産自動車株式会社 | Engine exhaust purification device |
DE19803828B4 (en) | 1998-01-31 | 2010-05-12 | Robert Bosch Gmbh | Method and device for assessing the conversion capability of a catalyst |
US6202406B1 (en) | 1998-03-30 | 2001-03-20 | Heralus Electro-Nite International N.V. | Method and apparatus for catalyst temperature control |
US6237330B1 (en) | 1998-04-15 | 2001-05-29 | Nissan Motor Co., Ltd. | Exhaust purification device for internal combustion engine |
US6128899A (en) | 1998-04-17 | 2000-10-10 | Honda Giken Kogyo Kabushiki Kaisha | Exhaust gas purification system for internal combustion engine |
US6189523B1 (en) | 1998-04-29 | 2001-02-20 | Anr Pipeline Company | Method and system for controlling an air-to-fuel ratio in a non-stoichiometric power governed gaseous-fueled stationary internal combustion engine |
US5877413A (en) | 1998-05-28 | 1999-03-02 | Ford Global Technologies, Inc. | Sensor calibration for catalyst deterioration detection |
JP3684854B2 (en) | 1998-07-02 | 2005-08-17 | 日産自動車株式会社 | Catalyst deterioration diagnosis device for internal combustion engine |
US6205773B1 (en) | 1998-07-07 | 2001-03-27 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification device for an internal combustion engine |
US6244046B1 (en) | 1998-07-17 | 2001-06-12 | Denso Corporation | Engine exhaust purification system and method having NOx occluding and reducing catalyst |
US6233925B1 (en) * | 1998-08-28 | 2001-05-22 | Toyota Jidosha Kabushiki Kaisha | Exhaust discharge control device for internal combustion engine |
US6079204A (en) | 1998-09-21 | 2000-06-27 | Ford Global Technologies, Inc. | Torque control for direct injected engines using a supplemental torque apparatus |
US6102019A (en) | 1999-01-07 | 2000-08-15 | Tjb Engineering, Inc. | Advanced intelligent fuel control system |
JP3225957B2 (en) * | 1999-02-02 | 2001-11-05 | トヨタ自動車株式会社 | Internal combustion engine |
JP3649034B2 (en) | 1999-03-25 | 2005-05-18 | 日産自動車株式会社 | Engine exhaust purification system |
US6327849B1 (en) * | 1999-06-08 | 2001-12-11 | Honda Giken Kogyo Kabushiki Kaisha | Exhaust gas purifying apparatus for internal combustion engine and controller for internal combustion engine |
JP3558017B2 (en) * | 2000-07-21 | 2004-08-25 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
-
2001
- 2001-06-19 US US09/884,331 patent/US6490860B1/en not_active Expired - Fee Related
-
2002
- 2002-05-29 DE DE10223984A patent/DE10223984A1/en not_active Withdrawn
- 2002-06-11 GB GB0213308A patent/GB2380432B/en not_active Expired - Fee Related
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110185708A1 (en) * | 2010-01-29 | 2011-08-04 | Eaton Corporation | Adaptive Desulfation Control Algorithm |
WO2014007749A1 (en) * | 2012-07-06 | 2014-01-09 | Scania Cv Ab | Method for estimating quantity of sulphur accumulated in exhaust after treatment system |
Also Published As
Publication number | Publication date |
---|---|
US6490860B1 (en) | 2002-12-10 |
GB2380432A (en) | 2003-04-09 |
GB0213308D0 (en) | 2002-07-24 |
GB2380432B (en) | 2004-11-24 |
DE10223984A1 (en) | 2003-01-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6499293B1 (en) | Method and system for reducing NOx tailpipe emissions of a lean-burn internal combustion engine | |
US6467259B1 (en) | Method and system for operating dual-exhaust engine | |
JP2526591B2 (en) | Air-fuel ratio control device for internal combustion engine | |
US6314724B1 (en) | Air-fuel ratio controller and method of controlling air-fuel ratio | |
US6763656B2 (en) | Method and apparatus for optimizing purge fuel for purging emissions control device | |
GB2380692A (en) | A method and system for controlling an internal combustion engine. | |
JP2004218541A (en) | Control device for internal combustion engine | |
US6604504B2 (en) | Method and system for transitioning between lean and stoichiometric operation of a lean-burn engine | |
US6792751B2 (en) | Exhaust gas purification device and method for diesel engine | |
US7640727B2 (en) | Combustion control for engine | |
US20020189235A1 (en) | Method and system for controlling a regeneration cycle of an emission control device | |
US6487849B1 (en) | Method and apparatus for controlling lean-burn engine based upon predicted performance impact and trap efficiency | |
US6490860B1 (en) | Open-loop method and system for controlling the storage and release cycles of an emission control device | |
US6487853B1 (en) | Method and system for reducing lean-burn vehicle emissions using a downstream reductant sensor | |
EP1617062B1 (en) | Air/fuel ratio control device for internal combustion engine | |
US6564544B2 (en) | Engine exhaust purification arrangement | |
US6374597B1 (en) | Method and apparatus for accessing ability of lean NOx trap to store exhaust gas constituent | |
US6546718B2 (en) | Method and system for reducing vehicle emissions using a sensor downstream of an emission control device | |
US6453666B1 (en) | Method and system for reducing vehicle tailpipe emissions when operating lean | |
US6360529B1 (en) | Method and apparatus for enabling lean engine operation upon engine start-up | |
US6708483B1 (en) | Method and apparatus for controlling lean-burn engine based upon predicted performance impact | |
KR101697852B1 (en) | Exhaust purification system of gas heat pump engine | |
JP4608758B2 (en) | Air-fuel ratio control device for internal combustion engine | |
US6650991B2 (en) | Closed-loop method and system for purging a vehicle emission control | |
JPS63113149A (en) | Idling speed control device for engine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FORD MOTOR COMPANY, MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FARMER, DAVID GEORGE;SURNILLA, GOPICHANDRA;CULLEN, MICHAEL JOHN;REEL/FRAME:011953/0001;SIGNING DATES FROM 20010529 TO 20010612 Owner name: FORD GLOBAL TECHNOLOGIES, INC., MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FORD MOTOR COMPANY;REEL/FRAME:011953/0512 Effective date: 20010613 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20061210 |